A Franklin man is under investigation for the alleged theft of Mitt and Ann Romney's tax returns from PricewaterhouseCoopers in September, a Channel 4 I-Team investigation has found. That suspect, MichaelMore >>

A Franklin man is under investigation for the alleged theft of Mitt and Ann Romney's tax returns from PricewaterhouseCoopers in September, a Channel 4 I-Team investigation has found.More >>

NASHVILLE, TN (WSMV) -

The Franklin man accused by the government of developing a scheme to convince the world he had stolen Mitt and Ann Romney's tax returns turned himself in to the Secret Service and pleaded not guilty in federal court, the Channel 4 I-Team has learned.

Michael Brown faces 12 criminal charges of mail fraud and extortion.

When the Channel 4 I-Team first revealed last November that Brown was the Secret Service's main suspect in the alleged crime, Brown said he did not steal the Romney's tax returns and was not a computer hacker.

In an unsealed indictment, the United States Attorney General's Office states Brown claimed to have hacked into Pricewaterhousecooper's Franklin office and stolen the Romney's tax return prior to 2010.

The indictment also reads that Brown was responsible for online postings and ransom notes that demanded $1 million or the Romney's tax returns would be released.

According to the indictment, government investigators found that Brown printed an internet map in August 2012 showing driving directions from his house to Pricewaterhousecooper's Franklin office.

The indictment stated that Brown used a friend's computer to print out the random letters sent to the political party headquarters and Pricewaterhousecooper's office.

The indictment did not say how investigators determined their accusations, but Brown confirmed to the Channel 4 I-Team after the Secret Service raided his home in September 2012 that agents took his computer equipment as well as the computer equipment of a friend.

"They [the Secret Service] made it very clear that they were absolutely certain that I was the mastermind behind the whole thing," Brown said in an interview with the Channel 4 I-Team in November 2012.

The indictment also stated that after the random notes went out, Brown visited approximately 300 websites that discussed the purported theft of the Romney's tax information.

The indictment marks the second time Brown has been investigated by the Secret Service and is the first time to be charged.

Brown's own cameras captured a 2009 Secret Service raid at his home. Brown was suspected of allegedly hacking into an insurance company's website but was never charged.

"This is the second time the Secret Service has thought you are responsible for some crime," asked chief investigative reporter Jeremy Finley in November 2012.

"I understand that the Secret Service is just doing its job. They are investigating for a crime. But at the same time I feel like I'm being profiled," Brown said.

Brown was released without bond, but if he fails to show up for any court appearance, he may have to pay $10,000 to the courts.